Long time Volvo owner but new to this forum. Recently found the "ideal" used car to buy. It's a 2015.5 T6 Platinum with only 16,500 miles as a personal lease. I had looked at it previously and went back with my wife yesterday, checkbook in hand ready to buy it. BUT....

When we went out for a test drive she immediately noticed a definite thumping from somewhere underneath the car (about halfway back) every time I accelerated from a stop. More noticeable with a faster start (but it didn't have to be crazy fast start to notice it.) Being the male, I immediately thought she was hearing things but that was not the case; she had nailed it. I went back and got the salesman and brought him for a ride; he agreed with us that there was something amiss, said it was probably the tires. I didn't buy that so I declined to proceed with the transaction until it got looked at by the Service Dept. Salesman called back several hours later and said that a drive shaft bushing was wearing and needed to be replaced and that couldn't be done until Mon or Tues. Told him to call me when the problem was resolved and I would come back and check it out.

My questions:
1) Does this sound like a plausible explanation for the symptom I described?
2) Is there anything in particular that might cause the bushing to wear at such low mileage? Is this a red flag about the car?
3) Is this a "typical" Volvo XC70 problem? (I have a 2005 XC70 with 150K miles and have not had this happen).

Car still has about 15 months of factory warranty but I really don't want to get into a situation where I buy a car and then have to fight over what's covered and what isn't.

Thank you.